A variety of reports suggest that, during a conference call this afternoon, President Obama probed House progressives to see just how flexible their demands are.

A source familiar with the call tells TPM that Obama asked the group to define their red line when they talk about a "robust public option."

NBC reports that Obama reminded the group that they enjoy the security of representing safely Democratic districts.

And progressive caucus co-chair Raul Grijalva (D-AZ) told Greg Sargent that Obama outright asked the participants how far they're willing to compromise on the public option.

All in all it appears very much as if the President is feeling out how willing the House will be to support a bill that falls short of their earlier demands for a Medicare-like public option available to all consumers without any triggers. As I reported earlier today, Obama's set to meet with progressive House leaders Tuesday ahead of his big health care speech before Congress. That's shaping up to be an extremely crucial meeting.